Exhaust mechanism



(No Model.)

J. D. SMITH. EXHAUST MECHANISM.

No. 404,739. Patented June 4, 1889.

UNIT D STATES PATENT OFFICE.

JOHN D. SMITH, OF MURFREESBOROUGH, TENNESSEE.

EXHAUST MECHANISM.

SPECIFICATION forming part of Letters Patent No. 404,739, dated June 4,1889. Application filed December 18, 1888. Serial No. 293,938. (Nomodel.)

To all 1072,0712 it may concern:

Be it known that I, JOHN D. SMITH, of Murfreesborough, in the county ofRutherford and State of Tennessee, have invented certain new and usefulImprovements in Attachments for Exhaust Mechanism; and I do herebydeclare the following to be a full, clear, and exact description of theinvention, such as will enable others skilled in the art to which itpertains to make and use it, reference being had to the accompanyingdrawings,which form part of this specification.

My invention relates to an improvement in attachments for exhaustmechanism; and the object of my invention is to place in the smokestacka pipe which is movable at its lower end in relation to theexhaust-pipe, whereby the exhaust-steam can be turned into the lower endof the movable pipe, which is contracted and perforated at its upper endfor the purpose of destroying the draft through the stack when the doorof the furnace is opened.

Figure 1 is a perspective of a boiler, partly in section, showing myattachment applied thereto. Fig. 2 is a vertical section taken throughthe stack.

A represents the boiler of a portable steamengine or locomotive, B itsstack, and O the exhaust-pipe leading from the cylinder of the engine.Extending horizontally through the stack, at anysuitable distance aboveits lower end, is the pivotal rod D,upon which the pipe F, having anumber of perforations through its upper end, is placed. Upon this rod,at each side of the pipe F, is placed a stop, G, in order to prevent thepipe from having any lateral movement in the stack and thus becomingdisplaced. Extending through the stack near its lower end is a revolvingshaft H, which is provided with a crank I, inside of the stack, foroperating the lower end of the pipe F, and a crank J at one end, towhich the operating-rod L is connected. The crank I inside of the stackis loosely connected to the lower end of the pipe F by means of a catch0, of either the form here shown or any other which will answer the samepurpose. This catch allows the crank I to move freely along the side ofthe pipe at the same time that the lower end of the pipe is movedlaterally, so as to bring it directly over the mouth of the exhaust-pipeC,

or move the end of the pipe F to one side, where the exhaust-steamescaping from the pipe 0 will not enter into the pipe F. Theoperating-rod L has the notches or recessesQ in it near its outer end,so as to catch upon the projection R, formed upon the top of the boiler,and thus hold the rod and the pipeF into any position into which theymay be adjusted. \Vhen the rod F is moved into the position shown insolid lines in Fig. 1, the exhauststeam is discharged directly into thelower end of the stack for the purpose of creating an increased draft inthe usual manner. When the pipe F has its lower end moved directly overthe end of the exhaust-pipe O, the exhaust-steam passes through the pipeF and is discharged into the stack through the perforations made in theupper end of the pipe. These perforations serve to break up the steaminto small jets, and, these jets being discharged into the stack at asuitable distance above its lower end, they do not affect the draft, asis the case when the exhaust-steam is discharged directly into the lower'end of the stack.

I do not limit my invention to the exact mechanism for operating thepipe F, for this may be varied at will without departing from the spiritof my invention.

This pipe applied to portable engines and locomotives serves toprotectthe flues and the interior of the fire-box, and it saves steam,fuel, and labor, and is a great protection against those fires whichoriginate from the sparks which are blown out of the stack. If the doorof the furnace is opened While the steam is being exhausted directlyinto the lower end of the stack, a great draftis created through thefurnace, and the cold air in passing through the furnace and boilerinjures both the fire-box and the flues by the sudden contraction whichit causes. As the pipe Fis to be moved over the exhaust-pipe C beforethe furnace-door is opened, the draft through the stack B is destroyed,and the fire-door may be opened and closed at leisure without the lossof steam or damage through the firebox or flues. When the fire is beingstirred, more sparks are detached from the burning fuel than at anyother time; but, as there is no current of air passing through them,they fall into the ash-box and do no harm. This attachment overcomes allcontraction and expansion of the fire-box and flues, as no cold air isadmitted through the fire-door, causing expansion and contraction eachtime the door is opened and closed; but an approximately uniform degreeof heat is retained at all times. As will be seen, the upper end of thepipe is contracted or has a small opening" through it, so as to send ajet of steam directly up through the stack for the purpose of carryingthe smoke and the exhausted steam. The upper end of the pipe should notbe left entirely open nor entirely closed, as an upward j ct of steam isvery necessary.

Having thus described my invention, I claim" The combination of thestack, the exhaustpipe, a pipe pivoted in the stack and having its lowerend movable in relation to the eX- haust-pipe, and a meehanism foradjusting the lower end of the movable pipe, the upper end of themovable pipe beingeontracted and perforated and thereby partiallyclosed, substantially as described.

In testimony whereof I alfix my signature in presence of two witnesses.

JOHN D. SMI'llI.

\Vitnesses:

\V. (LVFROS'JQV H. (Human.

